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11-14-2013, 01:15 AM   #1
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Lenses with at least 32mm image circle?

Which lenses have at least 32mm image circle? That's something that no lens specs I've ever seen say... Can anyone here mention any lenses? Are there any lenses that do that even if they're not FF lenses? the aps-c sensor is 25.1 16.7 so no aps-c lenses probably cover 32mm... but will all lenses that can also be used on FF cover a ⌀32mm circle?

11-14-2013, 03:40 AM   #2
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All medium format and large format lenses will able to handle this easily.

I have to ask, exactly what are you doing that requires lenses with large imaging circles? you have been asking some pretty bizarre questions on these forums lately.
11-14-2013, 04:03 AM   #3
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QuoteOriginally posted by tripodquest Quote
Which lenses have at least 32mm image circle? That's something that no lens specs I've ever seen say... Can anyone here mention any lenses? Are there any lenses that do that even if they're not FF lenses? the aps-c sensor is 25.1 16.7 so no aps-c lenses probably cover 32mm... but will all lenses that can also be used on FF cover a ⌀32mm circle?
Do some math, basic APS-C is 16x24 mm which if you consider the diagonal, which defines the image circle, it covers 28mm, but then add in that for Pentax, you also need to accommodate the shake reduction and it is likely that the lenses all cover out to 32mm or if not, only minor vignetting

Where does 32mm come from? This is an odd format, most closely related to a 24mm square frame on 35mm film
11-14-2013, 04:10 AM   #4
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QuoteOriginally posted by Digitalis Quote
All medium format and large format lenses will able to handle this easily.

I have to ask, exactly what are you doing that requires lenses with large imaging circles? you have been asking some pretty bizarre questions on these forums lately.
QuoteOriginally posted by Lowell Goudge Quote
Do some math, basic APS-C is 16x24 mm which if you consider the diagonal, which defines the image circle, it covers 28mm, but then add in that for Pentax, you also need to accommodate the shake reduction and it is likely that the lenses all cover out to 32mm or if not, only minor vignetting

Where does 32mm come from? This is an odd format, most closely related to a 24mm square frame on 35mm film
haha odd questions? I didn't think my questions were... questionable! RED 4k and 5k sensors have an image circle of 32mm... Thank you for the replies. the truth is, I'm trying to figure out what direction to take with my video needs. what camera... what format... I'm thinking about the effective focal lengths and field of view of many lenses, ones I own and ones I could buy, on different systems, I'm trying to see a bigger picture so I can put together something I can be happy with. that's all ps. I have to add: you both calling my questions weird/odd made me laugh so hard (in a happy way), thank you!

11-14-2013, 07:16 AM   #5
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For the record all full frame, and 35mm slr lenses cover a 43mm image circle, so they will do. The truth is, almost all interchangeable lenses will.

The question is, what sensor do you plan to use with them?
11-14-2013, 04:33 PM   #6
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Are you looking for lens options for RED DSMC systems?
11-14-2013, 05:27 PM   #7
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QuoteOriginally posted by Lowell Goudge Quote
For the record all full frame, and 35mm slr lenses cover a 43mm image circle, so they will do. The truth is, almost all interchangeable lenses will.

The question is, what sensor do you plan to use with them?
QuoteOriginally posted by cscurrier Quote
Are you looking for lens options for RED DSMC systems?
I just said RED above, did you both miss it? The scarlet-x has a sensor that needs a 32mm image circle. I'm not sure but I think the other RED cameras do as well, but I'm not sure about the expensive ones. Maybe cscurrier knows what sensors the different models have?
11-14-2013, 06:03 PM   #8
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I would suspect that all DA lenses in this thread marked with +++ can also manage it; whether you'd be happy with sharpness at the edges is another story!

11-14-2013, 06:07 PM   #9
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QuoteOriginally posted by jimr-pdx Quote
I would suspect that all DA lenses in this thread marked with +++ can also manage it; whether you'd be happy with sharpness at the edges is another story!
the edge sharpness is also the burning question, the lenses should optimally have an image circle of 40mm or larger for that reason, but I wrote 32mm because that's the minimum required, I thought people will figure out that more is better on their own. thank you for the link, I'll check it out.

not surprisingly, they only work from 18mm up. that's always the thing with lenses made for smaller formats, they might work but only at longer focal lengths.
11-14-2013, 06:42 PM   #10
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QuoteOriginally posted by tripodquest Quote
I just said RED above, did you both miss it? The scarlet-x has a sensor that needs a 32mm image circle. I'm not sure but I think the other RED cameras do as well, but I'm not sure about the expensive ones. Maybe cscurrier knows what sensors the different models have?
Yay RED! Fun cameras indeed. I shoot the Epic regularly for work.

The Scarlet and Epic MX sensors do indeed need a 32mm image circle. If you plan on upgrading to the Dragon... looks like a 35mm image circle is needed. So ultimately, any full frame lens will cover em!

On a little side note, a friend of mine just got a K mount to EOS adapter for his 5D, and we're currently renting a Canon mount for our Epic. Shortly before our crew had to ship overseas, I was finally able to slap my SMC Pentax-M 50mm f1.7 on to our Epic body. I only had a few minutes to play, but damn did it look sexy. Now to just convince the boss to let us get the Canon mount for our camera so I can shoot more with my Pentax glass.....
11-14-2013, 06:47 PM   #11
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QuoteOriginally posted by cscurrier Quote
Yay RED! Fun cameras indeed. I shoot the Epic regularly for work.

The Scarlet and Epic MX sensors do indeed need a 32mm image circle. If you plan on upgrading to the Dragon... looks like a 35mm image circle is needed. So ultimately, any full frame lens will cover em!

On a little side note, a friend of mine just got a K mount to EOS adapter for his 5D, and we're currently renting a Canon mount for our Epic. Shortly before our crew had to ship overseas, I was finally able to slap my SMC Pentax-M 50mm f1.7 on to our Epic body. I only had a few minutes to play, but damn did it look sexy. Now to just convince the boss to let us get the Canon mount for our camera so I can shoot more with my Pentax glass.....
hahaha, wow! that's great, thank you now I have hope I could use some of my glass on a scarlet-x some day too
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